Kentucky center Nerlens Noel (right) could be the top pick in the draft but teams are concerned about his recovery from a torn ACL.

Kentucky center Nerlens Noel was the presumed No. 1 choice for next week's NBA draft, but nobody could say for sure.

And nothing is settled yet.

The Cleveland Cavaliers have kept everyone guessing while they try to sort out their options after winning the NBA draft lottery for the second time in three years.

The Cavaliers hit a home run with point guard Kyrie Irving, selecting him No. 1 in the 2011 draft. He went on to win rookie of the year and was named an all-star in his second season.

But it's not so clear-cut this time.

The Cavaliers also are checking out Georgetown's Otto Porter, Indiana's Victor Oladipo and Maryland sophomore Alex Len, a 7-foot-1, 225-pound center from Ukraine.

Injuries suffered by both Noel and Len are making the evaluations difficult.

The 7-foot Noel suffered a torn left anterior cruciate ligament while playing for Kentucky in mid-February. He has been sidelined ever since and is not expected to play for his NBA team until January or possibly later.

And Len underwent surgery in May for a stress fracture in his left ankle, putting him out of action for four to six months.

But Len has interviewed with four lottery teams — Phoenix, New Orleans, Portland and Oklahoma City — and has interviews set up with Charlotte (No. 4 pick) and Cleveland.

At the draft combine in May, Len said he thought he could be the best player to come out of this draft.

But he recently told the Baltimore Sun, "What I meant is that I could be the best player among the big men."

Noel, who turned 19 years old in April, is a shot blocker and intimidating defender.

But scouts were worried when he weighed in at 206 pounds at the combine, although a recent report said he is up to 218.

And it hasn't helped Noel's stock that he has been unable to work out and show his athleticism on the court.

Noel is often compared to Milwaukee Bucks center Larry Sanders, who also had a huge upside and was a great shot blocker with a limited offensive game. Sanders emerged in his third season — nearly averaging a double-double and ranking second in the league in blocks — after being selected 15th in the 2010 draft.

But is a tremendous shot blocker worth the No. 1 pick? That is the question the Cavaliers must answer.

Noel and Len are the cream of the draft's center class, but there are other first-round prospects.

Among them are New Zealand native and Pittsburgh freshman Steven Adams, who is just 19; Duke senior center Mason Plumlee, who is 23; France's Rudy Gobert, who decided Monday to remain in the draft; and Brazil's 7-foot Lucas Nogueira, who will turn 21 in July.

Also in the mix are Senegalese center and Louisville junior Gorgui Dieng and 7-foot Kansas senior Jeff Withey, considered one of the best shot blockers in the draft.

Kelly Olynyk, a 7-foot junior from Gonzaga and Kamloops, British Columbia, could be used as a stretch power forward or center. He is an outstanding ball handler for a player his size and can step out to hit perimeter shots. The question marks for Olynyk are his rebounding ability and defense.